diff --git a/assets/static/__mocks__/localStorageMock.js b/assets/static/__mocks__/localStorageMock.js
index 9935e1d36..78e61825a 100644
--- a/assets/static/__mocks__/localStorageMock.js
+++ b/assets/static/__mocks__/localStorageMock.js
@@ -1,22 +1,21 @@
-// source: https://github.com/facebook/jest/issues/2098
+class LocalStorageMock {
 
-var localStorageMock = (function() {
-    var store = {};
+    constructor() {
+        this.store = {};
+    }
 
-    return {
-        getItem: function(key) {
-            return store[key] || null;
-        },
-        setItem: function(key, value) {
-            store[key] = value.toString();
-        },
-        clear: function() {
-            store = {};
-        }
-    };
+    getItem(key) {
+        return this.store[key] || null;
+    }
 
-})();
+    setItem(key, value) {
+        this.store[key] = value.toString();
+    }
 
-Object.defineProperty(window, "localStorage", {
-    value: localStorageMock
-});
+    clear() {
+        this.store = {};
+    }
+
+}
+
+module.exports = new LocalStorageMock();
diff --git a/assets/static/filters.js b/assets/static/filters.js
index 3a99f6d2b..a6fe35373 100644
--- a/assets/static/filters.js
+++ b/assets/static/filters.js
@@ -21,6 +21,7 @@ var selectors = {
     historyMenu: "#historyMenu"
 };
 var appendsEnabled = true;
+var historyStorage;
 const historyKey = "filterHistory";
 
 function addBadge(text) {
@@ -69,13 +70,11 @@ function setPause() {
 }
 
 function renderHistory() {
-    const storage = window.localStorage;
-
     var historicFilters = [];
 
     const currentFilterText = getFilters().join(",");
 
-    const history = storage.getItem(historyKey);
+    const history = historyStorage.getItem(historyKey);
     if (history) {
         historicFilters = history.split("\n");
     }
@@ -93,14 +92,12 @@ function appendFilterToHistory(text) {
     // require non empty text and enabled appends
     if (!text || !appendsEnabled) return false;
 
-    const storage = window.localStorage;
-
     // final filter list we'll save to storage
     var filterList = [ text ];
 
     // get current history list from storage and append it to our final list
     // of filters, but avoid duplicates
-    const history = storage.getItem(historyKey);
+    const history = historyStorage.getItem(historyKey);
     if (history) {
         const historyArr = history.split("\n");
         for (var i = 0; i < historyArr.length; i++) {
@@ -114,7 +111,7 @@ function appendFilterToHistory(text) {
     // truncate the history to up to 11 elements
     filterList = filterList.slice(0, 11);
 
-    storage.setItem(historyKey, filterList.join("\n"));
+    historyStorage.setItem(historyKey, filterList.join("\n"));
 }
 
 function setFilters() {
@@ -131,7 +128,8 @@ function setFilters() {
     unsee.triggerReload();
 }
 
-function init() {
+function init(historyStore) {
+    historyStorage = historyStore;
     var initialFilter;
 
     if ($(selectors.filter).data("default-used") == "false" || $(selectors.filter).data("default-used") === false) {
diff --git a/assets/static/filters.test.js b/assets/static/filters.test.js
index f9fc45edc..d01fb3c1e 100644
--- a/assets/static/filters.test.js
+++ b/assets/static/filters.test.js
@@ -1,5 +1,5 @@
 const $ = window.jQuery = require("jquery");
-require("./__mocks__/localStorageMock");
+const LocalStorageMock = require("./__mocks__/localStorageMock");
 
 test("filters addBadge()", () => {
     const filters = require("./filters");
@@ -7,7 +7,7 @@ test("filters addBadge()", () => {
 });
 
 test("default filter should be in history after setting filter to foo", () => {
-    localStorage.clear();
+    LocalStorageMock.clear();
     document.body.innerHTML =
         "<div class='input-group filterbar'>" +
         "  <div class='input-group-addon input-sm'>" +
@@ -26,7 +26,7 @@ test("default filter should be in history after setting filter to foo", () => {
     const filters = require("./filters");
 
     autocomplete.init();
-    filters.init();
+    filters.init(LocalStorageMock);
     filters.setFilters();
     filters.renderHistory();
 
@@ -35,11 +35,11 @@ test("default filter should be in history after setting filter to foo", () => {
     expect(elems.length).toBe(1);
     expect($(elems[0]).text().trim()).toBe("default");
     // we set foo, so that what should be in history
-    expect(localStorage.getItem("filterHistory")).toBe("foo");
+    expect(LocalStorageMock.getItem("filterHistory")).toBe("foo");
 });
 
 test("appended filtes should be present in history", () => {
-    localStorage.clear();
+    LocalStorageMock.clear();
     document.body.innerHTML =
         "<div class='input-group filterbar'>" +
         "  <div class='input-group-addon input-sm'>" +
@@ -58,7 +58,7 @@ test("appended filtes should be present in history", () => {
     const filters = require("./filters");
 
     autocomplete.init();
-    filters.init();
+    filters.init(LocalStorageMock);
     filters.setFilters();
     filters.renderHistory();
 
@@ -68,7 +68,7 @@ test("appended filtes should be present in history", () => {
     // default is used but default is always rendered so should be there
     expect($(elems[0]).text().trim()).toBe("default");
     // and that's what history should have
-    expect(localStorage.getItem("filterHistory")).toBe("default");
+    expect(LocalStorageMock.getItem("filterHistory")).toBe("default");
 
     // now we append more filters, so q=default becomes q=default,bar
     filters.addFilter("bar");
@@ -81,7 +81,7 @@ test("appended filtes should be present in history", () => {
     expect($(elems[0]).text().trim()).toBe("default");
     expect($(elems[1]).text().trim()).toBe("default");
     expect(
-        localStorage.getItem("filterHistory").split("\n")
+        LocalStorageMock.getItem("filterHistory").split("\n")
     ).toMatchObject(
         [ "default,bar", "default" ]
     );
@@ -98,7 +98,7 @@ test("appended filtes should be present in history", () => {
     expect($(elems[1]).text().trim()).toBe("default");
     expect($(elems[1]).text().trim()).toBe("default");
     expect(
-        localStorage.getItem("filterHistory").split("\n")
+        LocalStorageMock.getItem("filterHistory").split("\n")
     ).toMatchObject(
         [ "default,bar,@state=active", "default,bar", "default" ]
     );
diff --git a/assets/static/unsee.js b/assets/static/unsee.js
index 9157c25c2..49b5e1b9c 100644
--- a/assets/static/unsee.js
+++ b/assets/static/unsee.js
@@ -304,7 +304,7 @@ function setupPageVisibilityHandler() {
     }
 }
 
-function init() {
+function init(localStore) {
     progress.init();
 
     config.init({
@@ -318,7 +318,7 @@ function init() {
     summary.init();
     grid.init();
     autocomplete.init();
-    filters.init();
+    filters.init(localStore);
     watchdog.init(30, 60*15); // set watchdog to 15 minutes
 
     $(selectors.refreshButton).click(function() {
@@ -331,7 +331,7 @@ function init() {
     setupPageVisibilityHandler();
 }
 
-function onReady() {
+function onReady(localStore) {
     // wrap all inits so we can handle errors
     try {
         // init all elements using bootstrapSwitch
@@ -347,7 +347,7 @@ function onReady() {
         ui.setupModal();
         silence.setupSilenceForm();
         unsilence.init();
-        init();
+        init(localStore);
 
         // delay initial alert load to allow browser finish rendering
         setTimeout(function() {
@@ -381,4 +381,6 @@ exports.flash = flash;
 exports.parseAJAXError = parseAJAXError;
 exports.onReady = onReady;
 
-$(document).ready(onReady);
+$(document).ready(function() {
+    onReady(window.localStorage);
+});
diff --git a/assets/static/unsee.test.js b/assets/static/unsee.test.js
index 381c37848..c24ceee71 100644
--- a/assets/static/unsee.test.js
+++ b/assets/static/unsee.test.js
@@ -1,7 +1,7 @@
 const $ = require("jquery");
 const templatesMock = require("./__mocks__/templatesMock");
 const alertsMock = require("./__mocks__/alertsMock");
-require("./__mocks__/localStorageMock");
+const LocalStorageMock = require("./__mocks__/localStorageMock");
 
 jest.useFakeTimers();
 
@@ -51,7 +51,7 @@ if (alertsServer) {
         require("bootstrap/js/popover.js");
         alertsServer.start();
 
-        unsee.onReady();
+        unsee.onReady(LocalStorageMock);
         unsee.triggerReload();
         jest.runOnlyPendingTimers();
         // we should have 2 alerts